Drought level designation added to a Nelson water source by province
One of the city’s water sources has been given a severe drought designation by the province as hot and dry weather continues in the region.
According to BC River Forecast Centre (BCRFC) data, drought level five conditions now exist at the Anderson Creek reporting station near Nelson, as it recorded 10 per cent of its median flow over the last week.
BCRFC ranks drought levels from zero to five, with drought level five rated as the most severe, with “adverse impacts to socioeconomic or ecosystem values being almost certain.”
But the primary water source for the city is Five Mile Creek — located in the West Arm Wilderness Park — with Anderson and Selous Creek serving as its secondary seasonal sources.
Even so, one week ago the city instituted stage three watering restrictions for Nelsonites to limit usage and conserve the volume obtained from its primary source.
The Nelson water flow situation contrasts with the rest of the region. To the northwest a reporting station on the Slocan River near Crescent Valley reported 65 per cent of its median flow (drought level three).
Heading east the situation improves immensely, with Duhamel Creek at drought level zero (216 per cent of median flow), Redfish Creek near Harrop is 326 per cent of median flow (drought level zero) and Lemon Creek in mid-Slocan Valley at 91 per cent of median flow (drought level zero).
Despite the water flow, the BCRFC is cautioning that drought conditions will continue to impact the entire West Kootenay and Lower Columbia basin around Castlegar, which are currently at drought level four as a whole.
“Most of these areas have experienced little to no rainfall over the last five weeks, with continued dry weather in the forecast,” a release from the BCFRC on Wednesday noted.
The drought conditions impact people’s ability to water their yards and increase the threat of a interface wildfire near Nelson, but also freshwater fishing. On Thursday, due to increased stress to fish from low flows and high water temperatures, the province closed some creeks to fishing in Region 4, which includes Nelson.
Until Sept. 15 the following streams and all their tributaries are closed to fishing: Michel Creek (excluding Alexander Creek and its tributaries), Morrissey Creek, Lizard Creek, Coal Creek, Sand Creek and the St. Mary River (from the outlet of St. Mary Lake to its confluence with the Kootenay River), and all streams in management units 4-3 to 4-9 (except the main stem of the Columbia and Kootenay rivers).
Snow pack remains solid
Despite the drought conditions the West Kootenay snow basin index is fairly stable at 83 per cent of normal. Last year at this time, however, it was 128 per cent.
By June 1, approximately half of the accumulated snowpack had melted on average (according to data from automated snow weather stations).
“Due to several periods of very warm temperatures during spring, snowmelt rate has been slightly higher than normal this year,” the BCRFC reported. “The overall snowpack at all automated snow weather stations had dropped 60 per cent by June 1 from the peak snow accumulation.”
During the first week of June, a high streamflow advisory was issued for the West Kootenay due to snowmelt from snow remaining at higher elevations and high rainfall.
“Most of the larger stream systems with significant watershed area at high elevations have peaked from the recent events and are unlikely to reach these high flows from snowmelt alone,” the BCRFC website predicted.
• BC River Forecast Centre map of the region:
• Anderson Creek station seven-day flow and historical data:
Provincial areas currently under drought level four include:
• Thompson-Okanagan: the Salmon River, Coldwater River and Nicola River watersheds;
• the Kettle River and Lower Columbia Basin; and
• the Eastern Vancouver Island Basin and Gulf Islands.
In these areas, adverse impacts of drought on people, fish or ecosystems are likely.